The widespread availability of computer networks provides access to vast quantities of information. Computer networks, such as the Internet, can potentially connect a computer user, for example, to any of numerous sources of information. Consequently, people can obtain information about any number of topics of interest, including products, services, events, people, and concepts.
A conventional approach to access information over a computer network is to use an information retrieval system, such as a web search system or search engine. A web search system develops an index of items conveying information that is available over a computer network in advance of a user's request for information. The items are formatted so that they convey information when requested by a computer user. The items, for example, may be files containing information or web pages that can be accessed over the computer network. When the search engine receives a query, representing a user's request for information about a topic, the search engine selects one or more items by matching items in the index to the search query and provides the items to the user.
Web search systems have been configured to employ various strategies to provide relevant search results, so as to reduce the burden on users to generate succinct, effective search queries. One approach has been to enable search engines to engage in query recommendation or suggestion. This approach involves large data graphs that store data (as nodes) and rules that describe knowledge about the data. These data graphs can be bipartite, meaning that the nodes in the graph can be divided into two disjoint sets, with all edges going between the two sets. Bipartite graphs can be generated for use in web usage mining, which extracts implicit knowledge from data that capture user interactions with the world wide web. In this way, they enable formulations of query recommendations or suggestions.
The subject matter discussed in this Background should not be assumed to be prior art merely as a result of its mention in this section. Similarly, a problem mentioned in this Background or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art.